He's talking about fuses for the low-current auxiliary circuits. From the title, I thought he was talking about fuses in the battery and propulsion system. Fuses very rarely blow for random reasons today. There's been some progress since the "Lucas, Prince of Darkness" era.

The high-power system uses fuses because, if things overload there, you want power disconnected reliably and you want it to stay off. Lithium batteries do not handle overloads well. Not at all.